Color-mixing fixing device in which impact resilience of surface layer of fixing rotary member is 50% or less

Abstract

A color-mixing fixing device includes a first fixing rotary member, and a second fixing rotary member for forming a nip together with the first fixing rotary member. After toner images of a plurality of colors stacked on one surface of a recording medium are fixed by a nip, toner images of a plurality of colors stacked on the other surface of the recording medium are fixed by the nip, thereby forming full-color images on both the surfaces of the recording medium. Each of the first and second fixing rotary members has a surface rubber layer with an impact resilience of 50% or less.

What is claimed is:  
     
       1. A color-mixing fixing device comprising: 
       a first fixing rotary member have a surface silicone rubber layer and contacting with an unfixed image; and  
       a second fixing rotary member have a surface silicone rubber layer for forming a nip together with said first fixing rotary member,  
       wherein after toner images of a plurality of colors stacked on one surface of a recording medium are fixed at a nip, toner images of a plurality of colors stacked on the other surface of the recording medium are fixed at the nip, thereby forming full-color images on both the surfaces of the recording medium,  
       wherein each of the surface silicone rubber layer of said first and second fixing rotary members has an impact resilience of not more than 50% and a difference in the impact resilience between said surface rubber layers of said first and second fixing rotary members is within 5%, and  
       wherein the surface silicone rubber layer of said first fixing rotary member is thicker than that of the surface silicone rubber layer of said second fixing rotary member.  
     
     
       2. A device according to  claim 1 , wherein the impact resilience of said surface rubber layer of each of said first and second fixing rotary members is not less than 30%. 
     
     
       3. A device according to  claim 1 , wherein the difference in impact resilience between said surface rubber layers of said first and second fixing rotary members is within 3%. 
     
     
       4. A device according to  claim 1 , wherein both of said first and second fixing rotary members include internal heat sources.